car is misfiring bad at 1700rpm, video
#1
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car is misfiring bad at 1700rpm, video
car is a STOCk 1988 gxl. i have searched on this problem, but couldn’t find any solutions, in most cases the car had been modified.
ive been trying to pass smog, with no avail.
the car has a misfire at idle, also if i hold the rpm anywhere from 1k to 2k there is more misfires.
any help is appreciated.
thanks
ive been trying to pass smog, with no avail.
the car has a misfire at idle, also if i hold the rpm anywhere from 1k to 2k there is more misfires.
any help is appreciated.
thanks
Last edited by rotorpower27; 06-28-07 at 11:07 PM.
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replaced: plugs and O2 sensor.
im waiting for my new ngk spark plug wires to show up.
if i do somehow have the wires wrong, let me clarify.
the coil in the left front fender well area is for the bottom two spark plugs correct?
what else could cause a misfire?
im waiting for my new ngk spark plug wires to show up.
if i do somehow have the wires wrong, let me clarify.
the coil in the left front fender well area is for the bottom two spark plugs correct?
what else could cause a misfire?
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#10
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Sounds more like a spark-related misfire than fuel mixture. I'd change the plugs and make sure there aren't any plug wires touching each other or anything metal, especially no plug wires cable-tied together. A popular mistake. Run the engine at idle on a dark night and look for arcing anywhere along the plug wires/ coil towers/ plugs. Blip the throttle a few times, arcing can occur under load, especially on a cold engine when spark demand is greatest.
Also, is your hot idle always at 1750 rpm? do a propane check for vacuum leaks.
Also, is your hot idle always at 1750 rpm? do a propane check for vacuum leaks.
#11
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High hydrocarbons can be the result of overadvanced spark timing, ignition-related misfires, too rich fuel mixtures, and, believe it or not, too lean fuel mixtures. Lots of people don't get that last one though. I can explain it, but perhaps tomorrow. I'm off to bed.
#12
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Checked the wires, they are correctly installed. They have a plastic shield on them, but they are next to each other.
When my new ones arrive I will make sure to keep them apart.
["Also, is your hot idle always at 1750 rpm? Do a propane check for vacuum leaks."
No I had the idle set that way so I could walk around. I used some pliers kinda, basically if someone had their foot on the pedal. ]
I checked for fuel mixture by doing the propane trick, hooking it directly in line with a vac line, and the idle went up slightly with very little propane, any more and it started to bog, and from what I gather that’s about right.
Also shot some around any vac lines and it had no effect, so I don’t believe I have any vac leaks. I have changed as much vac line as I can with out damaging anymore fragile plastic.
I changed plugs two days ago. Question though, what plug is hotter the 9's or 7’s?
And 7’s on leading and 9’s on trailing, yes?
When my new ones arrive I will make sure to keep them apart.
["Also, is your hot idle always at 1750 rpm? Do a propane check for vacuum leaks."
No I had the idle set that way so I could walk around. I used some pliers kinda, basically if someone had their foot on the pedal. ]
I checked for fuel mixture by doing the propane trick, hooking it directly in line with a vac line, and the idle went up slightly with very little propane, any more and it started to bog, and from what I gather that’s about right.
Also shot some around any vac lines and it had no effect, so I don’t believe I have any vac leaks. I have changed as much vac line as I can with out damaging anymore fragile plastic.
I changed plugs two days ago. Question though, what plug is hotter the 9's or 7’s?
And 7’s on leading and 9’s on trailing, yes?
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i have other threads up that are related more towards the emissions filing part
link: https://www.rx7club.com/showthread.p...51#post7085951
but because there is a video on this one im getting much more attention, hehe
link: https://www.rx7club.com/showthread.p...51#post7085951
but because there is a video on this one im getting much more attention, hehe
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#18
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My car has that same problem. If I use very light throttle anywhere from 1500 - 2000 rpm the car revs up and returns to 1000. It makes for going into reverse slowly very awkward. Check all the basic stuff, TPS, BAC, O2, yadda yadda whatever. Let me know what you find out! :p
#19
Lots of rotors
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Hey! Your exhaust sounds exactly like mine... and I bet you paid a lot more for it too :-P. It's normal for higher mileage rotaries to do that, like mine. And in the second video- your tps (throttle position sensor) is probably badly mis-adjusted and/or it's shot and is leaking. Try replacing it with another one known to be good and it should go away. I've been through 2 tps's that had the 1500 rpm loop.
#21
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TPS can't leak. Impossible when there is nothing to leak out.
Sounds normal to me. If you didn't pass smog, check your emmisions equipment. Look in the FSM. I have noticed that the ACV check valve gets clogged up with carbon and gunk and either needs to be cleaned or replaced for it to function correctly.
Your bouncing idle is your TPS. Sounds to me like its not incorrectly adjusted or has a dead spot.
Check your TPS
http://howto.globalvicinity.com/gv_w...i=58&co=1&vi=1
Sounds normal to me. If you didn't pass smog, check your emmisions equipment. Look in the FSM. I have noticed that the ACV check valve gets clogged up with carbon and gunk and either needs to be cleaned or replaced for it to function correctly.
Your bouncing idle is your TPS. Sounds to me like its not incorrectly adjusted or has a dead spot.
Check your TPS
http://howto.globalvicinity.com/gv_w...i=58&co=1&vi=1
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i have pulled the tps off the car and have checked the entire sweep of its motion, it was fine.
as for the ACV, this part is connected to the driver side of the intake manifold correct?
as for the ACV, this part is connected to the driver side of the intake manifold correct?
#24
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Hey! Your exhaust sounds exactly like mine... and I bet you paid a lot more for it too :-P. It's normal for higher mileage rotaries to do that, like mine. And in the second video- your tps (throttle position sensor) is probably badly mis-adjusted and/or it's shot and is leaking. Try replacing it with another one known to be good and it should go away. I've been through 2 tps's that had the 1500 rpm loop.
Throttle Position Sensors do not leak. It is only a drum sensor...